SOLAR SHADING
On southern and western
exposures canvas awnings
minimize solar heat gain in
summer cooling months.
LIVE/ WORK/DOWNTOWN
By locating the home and
office on the same lot,
the daily commute has been
eliminated. Added to the
savings in gasoline is the time
gained that can be spent
on more productive and
fullfilling activities.
A downtown location encourages walking and bicycling which has health benefits as well as saving gasoline.
SIZE
One of the biggest impacts
on energy use is the size
of the building. Smaller
structures use less materials,
which saves energy in
production, transportation,
installation and maintenance.
Smaller structures take less
energy to heat and cool.
The residence here is only
1730 sf. but feels larger
due to high ceilings, openings
between floors, and a large
glass door to the exterior
which visually expands the room to include the courtyard.
The use of exterior space in our climate also allows for smaller
interior spaces.
INDOOR FINISH MATERIALS
Using structural materials
as finished materials reduces
the products that are
manufactured, shipped,
maintained and replaced.
Here, the Doug Fir roof
decking and beams are the
finished ceiling; no sheetrock.
The walls have a sanded
compound finish; no paint.
The floors are stained and
sealed concrete; no carpet.
Savings will extend into the future as the products that are not initially included will never need maintenance or replacement.
PASSIVE HEATING
A large sliding glass door
in the Great Room
combined with the dark
stained concrete floor allows
for solar gain and storage
in the winter. In the summer
a large retractable canvas
awning keeps the sun out.
PHOTOVOLTAICS
Between rebates, tax credits
(commercial) and depreciation,
the cost of photovoltaics
can be reduced to 25–30%
of original cost. In this case
the energy savings more than
paid for the monthly cost to
purchase the sytem.
PASSIVE COOLING CEILING FANS
Cassablanca type ceiling fans circulate air in the summer which provides a greater sense of comfort in warmer temperatures.
Again, with far less electricity use and corresponding cost than air conditioning.
PASSIVE COOLING NIGHT AIR FAN
When passive cooling via
the thermal chimney effect
is inadequate, 36" industrial
fans bring in large quantities
of cool night air. This is
technology borrowed from
the wine industry. These
fans allowed air conditioning
to be eliminated. The
electricity required to run the
fans is a small fraction of
the cost to power AC.
PASSIVE COOLING THERMAL CHIMNEY
Openings in the floors
create a thermal chimney
(hot air rising) that exhausts
hot air high in the space
and pulls in cooler air from
outside. Outside air cools
the thermal mass in the
structure which then is
able to absorb heat the
following day keeing
temperatures comfortable.
ON DEMAND GAS BOILER
A 98% efficient instant gas
boiler heats water for both
radiant heating as well as
domestic use. Eliminating the
tank associated with
conventional water heaters
means there is no energy
wasted in heating stored
water.
THERMAL MASS
Concrete slabs at grade and
on the upper floors add mass
to the interior which absorbs
daytime heat in the summer
and provides the mass for
radiant heating in the winter.
Insulation between the slab
and exterior stem wall
reduce heat loss. Use of 5/8"
sheetrock vs. 1/2" adds mass
as well.
DAYLIGHTING
Windows properly placed
reduce the need for electric
lighting during daylight hours.
In addition to reducing
direct energy usage, this
lowers the need for cooling
in the summer.
LOW MAINTENANCE EXTERIOR MATERIALS
The exterior materials are
brick, corrugated steel,
rusting cor–ten steel, and
Hardipanel siding. Only the
siding will ever need
maintenance (repainting).
LOW WATTAGE BULBS
The use of fluorescent light
fixtures and dimmers
significantly reduce the
electricity used for lighting.
RECYCLED MATERIALS
The use of salvaged
materials reduces the need
to manufacture new products
and saves room in landfills.
The front door to the house
and garage, and this gate
were all salvaged. Use of
these types of components
can also add charm to a new
project.
HIGH PERFORMANCE GLASS
The use of dual glazing,
heat blocking films, and inert
gasses between the glass
panels significantly
reduce the summer heat
gain.
RADIANT HEAT
Hot water is circulated in
plastic tubing within the slab
to warm the mass of the
floor. The mass moderates
and stores the heat.
Radiant heat provides the
same level of comfort with
lower air temperatures
compared to forced air
heating.
NATIVE LANDSCAPING
The use of plants
that are native or have
low water needs enabled the
use of drip irrigation which
conserves water.
Sustainability
Our approach to sustainable design begins with the site. Is it an urban infill location or a large property in the country? How do the solar orientation, topography and prevailing winds interact with access to the site and views? How much involvement does the Client want in operation of the systems? How interested is the Client in long term or life cycle costs as opposed to the initial cost of the project. What is an acceptable payback period for investments in energy saving features? These are questions we ask as we begin the design process. Sustainability is built into the project from its inception, not added on at the end.
We have been doing this kind of design long before the phrases ‘Green Building’ and ‘Global Warming’ became part of our regular vocabulary.
We will highlight our recent 205 Center St. project to illustrate strategies that can be employed in reducing energy use.
205 Center St. is a live/ work project that includes the office of Alan B. Cohen, Architect, his wife’s painting studio, and their residence. Nothing in 205 Center is particularly exotic. Energy savings are realized by making some lifestyle choices, incorporating a few routines into one’s daily life (ie. opening and closing windows), and with the use of ‘off–the–shelf’ components.
Prior to moving into 205 Center we lived in a house and I worked in an office built in the 60’s. Both are similar in size to 205 Center St. The office was in Santa Rosa, CA and just over a 17 mile one way commute from our home in Healdsburg. It is interesting to compare the energy usage before and after 205 Center. Natural gas (space and water heating and cooking), electricity (air conditioning, lights, fans, pumps, appliances, equipment), and gasoline (auto and truck fuel) were converted to BTUs (British Thermal Units) in order to compare overall energy use. We reduced our use by over 70% after moving to 205 Center St. See the attached Comparison of Energy Use for the data.
Here is a link to a video on this project produced by FairCompanies.com